We've discussed this question of "why aren't Christians today producing more good art than they are?" from time to time here at TC. The Touchstone article, which quotes heavily from the writings of Flannery O'Connor, narrows in on one big problem with Christian literature today:

O’Connor understood that good writers do not simply parrot these [religious] insights; they must take this doctrinal understanding and apply it to the concrete realities of human life. “Your beliefs will be the light by which you see, but they will not be what you see and they will not be a substitute for seeing.”

When we do not understand this distinction, Christian fiction becomes mere religious propaganda. “The sorry religious novel comes about when the writer supposes that because of his belief, he is somehow dispensed from the obligation to penetrate concrete reality.” Doctrine is a light to see human experience by, not a formula to be dressed up in a fictional disguise.

In other words, Christian writers are falling into the trap of simply dressing up and repeating their own beliefs, rather than using those beliefs to inform their exploration of the world and human behavior.

Food for thought. (And as a side note: I'd love to see an article tackle this subject by looking at the works and ideas of some of the other great Christian writers mentioned in the article: Philip Sidney, Edmund Spenser, George Herbert, T. S. Eliot, Graham Greene, Aleksander Solzhenitsyn, etc. Flannery O'Connor, Tolkien, Chesterton, and Lewis references are starting to become awfully familiar when this debate comes up; for variety's sake, I'd enjoy hearing about some of the other greats, and how their faith inspired their writing.)